Homebrew PCBs

I receive messages from this board in daily digest form. My etching
interest involves my small scale model railroad products business, not
PCB development and production. Everything I do (or hope to do) in
etching requires a double-sided approach.

So, usually, I quickly scan the digest messages rather than read them
in detail. But, I'm aware that you, Stefan, and others are working
hard to discover a way to economically and efficiently develop a
"home" (meaning small) etching operation.

I've got one that is virtually complete. It involves:

1) Power spray etching unit -- home built from plans found on Randy
Gordon-Gilmore's home page. Randy, a (mechanical?) engineer, has
worked through three iterations of etching machinery, and his home
pages contain great info. No doubt a number of members here know all
about Randy's etching developments.

2) Suitcase-sized UV vacuum exposure unit from (name escapes me at the
moment).

3) FeCl-based chemical etching.

4) Photo-resist (roll) from Think-n-Tinker.

5) Trace printing -- Have explored professional 2400 dpi output on
transparencies (excellent, excellent quality), but in my neck of the
woods there aren't many sources for this since direct-to-press
printing is so common. Have used other, acceptable printing methods, too.

My main problems to date with the system I have put together:

1) Adequate support for brass sheet, which needs to be suspended in
the middle of the tank and rotated while the power spray heads are
doing their thing.

2) Laminating photo resist to brass sheeting bubble free (the brass
sheets are cleaned immaculately; I'm well aware of the critical need
for this).

If I can find solutions for these problems, I'll use this system for
prototyping work mainly; production work will be done at a commercial
site, I think.

Sorry. Let me get to the point of this post.

If there's interest here from members, I would like to post to the
Files section a step-by-step description of how I built this system
and what devices and materials the system is composed of. This might
do two things:

1) Give some of you a pretty complete picture of what a home etching
system looks like, generally, and how to go about constructing and
operating such a system; and, in return,

2) People here on the list might make suggestions about how I can
improve the system I have and correct the problems I have with my
system as it now exists. I would make corrections and report back on
how well they work.

Please let me know if there's enough interest here for me to pursue
this from my end; it'll require quite a bit of time, and I'd rather
not get such a project underway without sufficient interest from
persons here on the list.

Thanks much,

-Brian

Brian Chapman
Cedar Rapids, Iowa


---

Brian,

I think I speak for most when I say 'Please post ANYTHING you can come up
with'.

Even if someone does not use the same etching technique as you do, does not
mean they cannot extract some useful trick that they require in another
technique.

Sometimes, new techniques are developped by mixing and matching steps from
several dfferent techniques.  You just never know what someone might find in
your tutorial.  It might even be for a process totally unrelated to etching;
like drilling, placing parts or stamping (via pins).

Just like you do with the list, people skim through and look for anything
they can use for themselves.

Robert
:)



-----Message d'origine-----
De : Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] De
la part de Brian Chapman
Envoyé : juin 6 2005 12:43
À : Homebrew_PCBs@yahoogroups.com
Objet : [Homebrew_PCBs] Etching project - Any interest here? . . .


If there's interest here from members, I would like to post to the Files
section a step-by-step description of how I built this system and what
devices and materials the system is composed of. This might do two things:

1) Give some of you a pretty complete picture of what a home etching system
looks like, generally, and how to go about constructing and operating such a
system; and, in return,

2) People here on the list might make suggestions about how I can improve
the system I have and correct the problems I have with my system as it now
exists. I would make corrections and report back on how well they work.

Please let me know if there's enough interest here for me to pursue this
from my end; it'll require quite a bit of time, and I'd rather not get such
a project underway without sufficient interest from persons here on the
list.

Thanks much,

-Brian

Brian Chapman
Cedar Rapids, Iowa


---








Be sure to visit the group home and check for new Bookmarks and files:
http://groups.yahoo.com/group/Homebrew_PCBs 
Yahoo! Groups Links

On Mon, 06 Jun 2005 18:42:53 +0200, Brian Chapman  
<cornbeltroute@...> wrote:

> 1) Power spray etching unit -- home built from plans found on Randy
> Gordon-Gilmore's home page. Randy, a (mechanical?) engineer, has
> worked through three iterations of etching machinery, and his home
> pages contain great info. No doubt a number of members here know all
> about Randy's etching developments.


Hey the page of R.G. is interesting, didn't know that one.
<http://www.prototrains.com/>

He uses a pump to spray the etchant. too bad i didn't buy that all  
glass/teflon chemical pump on ebay..


I have terminated the rotary etcher a while back due to various problems,  
and it will be a while before i attempt a spray etcher again, but i'll  
still be very interested to hear about your system.

Also, the photo-process stuff is sure interesting for many here, as it is  
basically the same problems with PCBs you have/had to solve.

It will be great to read more about your setup, and i think there are  
people here that know how to solve the bubble-problem with laminate.

ST

OK, unless someone tells me 'no,' I'll go ahead with my idea here. I'm
hoping to get as much as I give, so I'm looking forward to it. Thanks.

-Brian

Brian Chapman
Evansdale, Iowa


---

On Tue, 07 Jun 2005 00:32:45 +0200, Brian Chapman  
<cornbeltroute@...> wrote:

> OK, unless someone tells me 'no,' I'll go ahead with my idea here. I'm
> hoping to get as much as I give, so I'm looking forward to it. Thanks.
> -Brian
> Brian Chapman
> Evansdale, Iowa


If some one tells you no, just ignore ;-)
Well, maybe you shouldn't ignore Steve the listowner, but everyone else...

ST

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan" 
<stefan_trethan@g...> wrote:
> On Tue, 07 Jun 2005 00:32:45 +0200, Brian Chapman  
> <cornbeltroute@m...> wrote:
> 
> > OK, unless someone tells me 'no,' I'll go ahead with my idea 
here. I'm
> > hoping to get as much as I give, so I'm looking forward to it. 
Thanks.
> > -Brian
> > Brian Chapman
> > Evansdale, Iowa
> 
> 
> If some one tells you no, just ignore ;-)
> Well, maybe you shouldn't ignore Steve the listowner, but everyone 
else...
> 
> ST

I'm Interested, what project do you have in mind?

Anita

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
> On Tue, 07 Jun 2005 00:32:45 +0200, Brian Chapman  
> <cornbeltroute@m...> wrote:
> 
> > OK, unless someone tells me 'no,' I'll go ahead with my idea here. I'm
> > hoping to get as much as I give, so I'm looking forward to it. Thanks.
> > -Brian
> > Brian Chapman
> > Evansdale, Iowa
> 
> 
> If some one tells you no, just ignore ;-)
> Well, maybe you shouldn't ignore Steve the listowner, but everyone
else...
> 
> ST

If someone tells Brian "no", -I'll- have something to say about it! ;')

Brian, don't forget I've also started the Homebrew_PCBs_Archives list,
so we have more space for Files and Photos over there.

A limitation of Yahoo Files and Photos: you can't link directly to a
particular file or photo. The upshot is if you try and upload a
website with images, it won't display the images.

If you need to put it up as a webpage(s), let me know as I have some
space on my site, polyphoto.com

Steve Greenfield, the listowner

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
> On Tue, 07 Jun 2005 00:32:45 +0200, Brian Chapman  
> <cornbeltroute@m...> wrote:
> 
> > OK, unless someone tells me 'no,' I'll go ahead with my idea here. I'm
> > hoping to get as much as I give, so I'm looking forward to it. Thanks.
> > -Brian
> > Brian Chapman
> > Evansdale, Iowa

Whoops, did I give the link to the Archives list?

http://groups.yahoo.com/group/Homebrew_PCBs_Archives/

Steve Greenfield

Stefan Trethan wrote:
> On Mon, 06 Jun 2005 18:42:53 +0200, Brian Chapman  
> <cornbeltroute@...> wrote:
> 
> 
>>1) Power spray etching unit -- home built from plans found on Randy
>>Gordon-Gilmore's home page. Randy, a (mechanical?) engineer, has
>>worked through three iterations of etching machinery, and his home
>>pages contain great info. No doubt a number of members here know all
>>about Randy's etching developments.
> 
> 
> 
> Hey the page of R.G. is interesting, didn't know that one.
> <http://www.prototrains.com/>
> 
> He uses a pump to spray the etchant. too bad i didn't buy that all  
> glass/teflon chemical pump on ebay..
> 

Most small chemical pumps do not have the pressure required for optimum 
nozzle performance, which is > 1 Bar (100kPa). These include magnetic 
drives. Yea sure you see magnetic drive pumps in professional pray 
equipment but take note at the size/price of these pumps. I've did a LOT 
of research on pumps when building my hobby CuCl2 spray etcher and the 
best (only) pump I've found suitable was the 12V Flojet brand pumps sold 
for caravan use.

Adam

On Tue, 07 Jun 2005 01:38:12 +0200, Adam Seychell  
<a_seychell@...> wrote:

>
> Most small chemical pumps do not have the pressure required for optimum
> nozzle performance, which is > 1 Bar (100kPa). These include magnetic
> drives. Yea sure you see magnetic drive pumps in professional pray
> equipment but take note at the size/price of these pumps. I've did a LOT
> of research on pumps when building my hobby CuCl2 spray etcher and the
> best (only) pump I've found suitable was the 12V Flojet brand pumps sold
> for caravan use.
> Adam


ok.
I also wasn't impressed with the max. height rating (pressure), that's why  
i didn't buy then.

thanks

ST

On Tue, 07 Jun 2005 09:34:46 +0200, Stefan Trethan <stefan_trethan@...>  
wrote:

>> Most small chemical pumps do not have the pressure required for optimum
>> nozzle performance, which is > 1 Bar (100kPa). These include magnetic
>> drives. Yea sure you see magnetic drive pumps in professional pray
>> equipment but take note at the size/price of these pumps. I've did a LOT
>> of research on pumps when building my hobby CuCl2 spray etcher and the
>> best (only) pump I've found suitable was the 12V Flojet brand pumps sold
>> for caravan use.
>> Adam


Say Adam, i saw by chance they are selling shurflo pumps at ebay germany,  
but no Flojet.
I think to remember you had something to say about those. Since i have  
lost all my mail in the harddisk failure i can't look it up. (well, i  
could use the archives but yahoo frightens me these days...)

If you know the shurflo, please comment.
I'm not actively looking for a pump right now, but i'd rather keep my eyes  
open than buy one expensive when i want to have another go at the sprayer.

thanks

ST

(P.S.: I'm just now making PCBs with silicone paper, maybe have some new  
results later on. Things looking good.)

Stefan Trethan wrote:
> On Tue, 07 Jun 2005 09:34:46 +0200, Stefan Trethan <stefan_trethan@...>  
> wrote:
> 
> 
>>>Most small chemical pumps do not have the pressure required for optimum
>>>nozzle performance, which is > 1 Bar (100kPa). These include magnetic
>>>drives. Yea sure you see magnetic drive pumps in professional pray
>>>equipment but take note at the size/price of these pumps. I've did a LOT
>>>of research on pumps when building my hobby CuCl2 spray etcher and the
>>>best (only) pump I've found suitable was the 12V Flojet brand pumps sold
>>>for caravan use.
>>>Adam
> 
> 
> 
> Say Adam, i saw by chance they are selling shurflo pumps at ebay germany,  
> but no Flojet.
> I think to remember you had something to say about those. Since i have  
> lost all my mail in the harddisk failure i can't look it up. (well, i  
> could use the archives but yahoo frightens me these days...)
> 
> If you know the shurflo, please comment.
> I'm not actively looking for a pump right now, but i'd rather keep my eyes  
> open than buy one expensive when i want to have another go at the sprayer.
> 
> thanks
> 
> ST


No probs, I'm glad to help someone else avoid having to go through all 
the trial and error I did. I found two main brands of 12V "on demand" 
diaphragm pumps for water supply in caravans. Diaphragm pumps are more 
efficient, and more suited to high pressure/low volume than centrifugal 
impeller pumps. This means for our "small" sized pumps a diaphragm type 
is a better choice. The two brands are Shurflo, and Flojet. 
Unfortunately all the Shurflo's are built the same and are not FeCl3 
resistant only because they use stainless steel screws to hold the 
little plastic pistons on the diaphragm. The Flojet apparently does not 
have this drawback with all materials are resistant. Here is a copy of 
the reply I got from Flojet customer support when asking about chemical 
compatibility.

"The wetted materials are:

- Polypro/galss plastic for the housing and check valve assembly
- Poly/glass inner piston
- Santoprene diaphragm
- EPDM check valves
- EPDM switch diaphragm
- Santoprene seal ferrules

Rgds,
Roy"


I bought a Shurflo pump over the Flojet because at the time I didn't 
know better and they had more details on the datasheet. Considering the 
Shurflo flaw, it lasted a good 3 months before the SS screws finally 
gave way in the CuCl2. Luckily for me, only the ball bearing was 
damaged, so I was able to remove the last remaining threads of the SS 
screws and replace them with plastic coated machine screws.  I managed 
to save my Shurflo pump and its been in operation for a few months now. 
The Flojet should be ok.

http://www.flojet.com/prodInfo/overview/81000-233_ds.pdf

There are more powerful models than this one but the price doubles 
because they are considered "industrial". I can't see any major 
differences between them that would justify the price jump. In any case, 
you have to choose the right nozzles to get the best performance from 
your pump. Mine is operating at 200 kPa (2.0 Bar) , which was chosen for 
maximum power transfer without overloading the pump motor. Electrical 
power = 12.5V @ 6.5A. Running time approximately 1/2 hour before case 
temperature rise reaches 60\ufffdC. Etching time normally is only a few 
minutes however.

For your nozzles, see http://www.spray.com  Considering I'm in Australia 
it only took two weeks to order three nozzles via their Australian 
representative ( A$10/nozzle). I was surprised to learn that the spray 
nozzle business is setup for selling small quantities. The factory had 
to especially make my nozzles because they didn't have them in stock, 
anywhere.

Adam

So, if i only would get a shurflo, what screws would that be that would  
need replacing?
I still have some titanium rod round here that i might get machined, or  
buy titanium screws....

thanks

ST

>
> No probs, I'm glad to help someone else avoid having to go through all
> the trial and error I did. I found two main brands of 12V "on demand"
> diaphragm pumps for water supply in caravans. Diaphragm pumps are more
> efficient, and more suited to high pressure/low volume than centrifugal
> impeller pumps. This means for our "small" sized pumps a diaphragm type
> is a better choice. The two brands are Shurflo, and Flojet.
> Unfortunately all the Shurflo's are built the same and are not FeCl3
> resistant only because they use stainless steel screws to hold the
> little plastic pistons on the diaphragm. The Flojet apparently does not
> have this drawback with all materials are resistant. Here is a copy of
> the reply I got from Flojet customer support when asking about chemical
> compatibility.
>
> "The wetted materials are:
>
> - Polypro/galss plastic for the housing and check valve assembly
> - Poly/glass inner piston
> - Santoprene diaphragm
> - EPDM check valves
> - EPDM switch diaphragm
> - Santoprene seal ferrules
>
> Rgds,
> Roy"
>
>
> I bought a Shurflo pump over the Flojet because at the time I didn't
> know better and they had more details on the datasheet. Considering the
> Shurflo flaw, it lasted a good 3 months before the SS screws finally
> gave way in the CuCl2. Luckily for me, only the ball bearing was
> damaged, so I was able to remove the last remaining threads of the SS
> screws and replace them with plastic coated machine screws.  I managed
> to save my Shurflo pump and its been in operation for a few months now.
> The Flojet should be ok.
>
> http://www.flojet.com/prodInfo/overview/81000-233_ds.pdf
>
> There are more powerful models than this one but the price doubles
> because they are considered "industrial". I can't see any major
> differences between them that would justify the price jump. In any case,
> you have to choose the right nozzles to get the best performance from
> your pump. Mine is operating at 200 kPa (2.0 Bar) , which was chosen for
> maximum power transfer without overloading the pump motor. Electrical
> power = 12.5V @ 6.5A. Running time approximately 1/2 hour before case
> temperature rise reaches 60\ufffdC. Etching time normally is only a few
> minutes however.
>
> For your nozzles, see http://www.spray.com  Considering I'm in Australia
> it only took two weeks to order three nozzles via their Australian
> representative ( A$10/nozzle). I was surprised to learn that the spray
> nozzle business is setup for selling small quantities. The factory had
> to especially make my nozzles because they didn't have them in stock,
> anywhere.
>
> Adam

On Thu, 09 Jun 2005 10:48:43 +0200, Adam Seychell  
<a_seychell@...> wrote:

>
> For your nozzles, see http://www.spray.com  Considering I'm in Australia
> it only took two weeks to order three nozzles via their Australian
> representative ( A$10/nozzle). I was surprised to learn that the spray
> nozzle business is setup for selling small quantities. The factory had
> to especially make my nozzles because they didn't have them in stock,
> anywhere.
> Adam

What nozzles did you use, i was looking at their page and they have 2 or 3  
different ones ;-)

I will not have time to build a sprayer any time soon, but reason i'm  
asking about it is that damn bubbler hose has apparently clogged up in the  
few weeks i wasn't using it. It was all nice and even at fist, but it is a  
nightmare again now.

how would it be possible to make a compact sprayer?


ST

Stefan Trethan wrote:
> On Thu, 09 Jun 2005 10:48:43 +0200, Adam Seychell  
> <a_seychell@...> wrote:
> 
> 
>>For your nozzles, see http://www.spray.com  Considering I'm in Australia
>>it only took two weeks to order three nozzles via their Australian
>>representative ( A$10/nozzle). I was surprised to learn that the spray
>>nozzle business is setup for selling small quantities. The factory had
>>to especially make my nozzles because they didn't have them in stock,
>>anywhere.
>>Adam
> 
> 
> What nozzles did you use, i was looking at their page and they have 2 or 3  
> different ones ;-)

That took a while to decide too. The web site lead me to the KYNAR 
VeeJet series:
  http://www.spray.com/catalogs/sg_EtchingRinsing.asp

I was able to find what type of nozzles typically used by spray etch 
machinery manufactures. For fan type nozzles the fan angle is between 
50\ufffd and 80\ufffd. I decided on 65\ufffd angle.
As for the nozzle size, I had to plot a graph showing pressure vs flow 
rate for both the pump and nozzle. Where the two graphs intersect is 
where the operating point is. After some shuffling around of figures , I 
went for three "size 8" nozzles that gives 6.2L/min at pressure of 1.8 
bar  and specific gravity of 1.35, pump voltage 12.0V.




> 
> I will not have time to build a sprayer any time soon, but reason i'm  
> asking about it is that damn bubbler hose has apparently clogged up in the  
> few weeks i wasn't using it. It was all nice and even at fist, but it is a  
> nightmare again now.
> 
> how would it be possible to make a compact sprayer?
> 

nope. compact is not possible. As for simplicity I like the idea from 
Randy Gordon Gilmore, where the only mechanical moving parts is the pump 
itself. Then you might use a full cone nozzle and have the PCB and 
nozzle stationary. But the question is will you gain a lot from this 
method over conventional bubble etching ? I can't answer this question 
because I haven't seen results from this method. It may be possible to 
optimize your bubble etcher. e.g bigger air pump and larger bubbles.

Hi,


My drills are all without the little plastic rings, so i bought a small  
lot with rings in the hopes of using them.
How can those rings be set? does it work with a metal tube and a little  
hammer?

Also, if somebody knows a inch/metric PCB drill conversion table (with the  
#), please let me know. it isn't that important as i can easily calculate  
it myself, but if you know a url...

ST

In a message dated 6/10/2005 6:25:17 A.M. Central Daylight Time,  
stefan_trethan@... writes:

How can  those rings be set? does it work with a metal tube and a  little 
hammer?<<
No, ST.  Use a small press.  Need not be a precision  manufactured thing, 
just a bit of bar-stock with an axle through the end, and a  flat surface upon 
which to place your work-piece.  Using a hammer will  surely damage the bits!

Also, if  somebody knows a inch/metric PCB drill conversion table (with the 
#),  please let me know. it isn't that important as i can easily calculate it  
myself, but if you know a url...<<
If you mean the American "Drill-numbering system", it cannot  be 
"calculated".  These numbers are quite random, and the ONLY thing  "regular" is that the 
size INCREASES as the number DECREASES.  A "Chart"  with the diameters in both 
inch and metric is surely available.  If I had a  scanner, I'd find one and 
send it to you, but I do NOT have a scanner, and, as  there would be THOUSANDS 
of characters (#'s) to type, and I am very, very lazy,  sorry!                  
  Jan  Rowland





[Non-text portions of this message have been removed]

On Jun 10, 2005, at 11:24 AM, JanRwl@... wrote:
................
Also, if  somebody knows a inch/metric PCB drill conversion table  
(with the
#),  please let me know. ........

http://www.engineersedge.com/drill_sizes.htm

[Non-text portions of this message have been removed]

ST,
I have one in an excel spreadsheet if that will help. I can either send it 
to you or upload as you desire.

bubba

At 02:24 PM 6/10/2005, you wrote:
>In a message dated 6/10/2005 6:25:17 A.M. Central Daylight Time,
>stefan_trethan@... writes:
>
>How can  those rings be set? does it work with a metal tube and a  little
>hammer?<<
>No, ST.  Use a small press.  Need not be a precision  manufactured thing,
>just a bit of bar-stock with an axle through the end, and a  flat surface 
>upon
>which to place your work-piece.  Using a hammer will  surely damage the bits!
>
>Also, if  somebody knows a inch/metric PCB drill conversion table (with the
>#),  please let me know. it isn't that important as i can easily calculate 
>it
>myself, but if you know a url...<<
>If you mean the American "Drill-numbering system", it cannot  be
>"calculated".  These numbers are quite random, and the ONLY 
>thing  "regular" is that the
>size INCREASES as the number DECREASES.  A "Chart"  with the diameters in 
>both
>inch and metric is surely available.  If I had a  scanner, I'd find one and
>send it to you, but I do NOT have a scanner, and, as  there would be 
>THOUSANDS
>of characters (#'s) to type, and I am very, very 
>lazy,  sorry!
>   Jan  Rowland
>

Bubba

OLDER THAN DIRT
Country Bubba
(Actually the inventor of Country and Bubba)
In God We Trust

LaGrange, GA

http://bellsouthpwp.net/A/r/Arts_home_page/cnc/  

[Non-text portions of this message have been removed]

Stefan,

For a drill bit size chart try:

<http://drillbitcity.com/images/charts/drill_bit_comp_chart.pdf>

Bob

> Hi,
> 
> 
> My drills are all without the little plastic rings, so i bought a
> small  lot with rings in the hopes of using them. How can those rings
> be set? does it work with a metal tube and a little  hammer?
> 
> Also, if somebody knows a inch/metric PCB drill conversion table (with
> the  #), please let me know. it isn't that important as i can easily
> calculate  it myself, but if you know a url...
> 
> ST
> 
> 
> ------------------------ Yahoo! Groups Sponsor
> --------------------~--> What would our lives be like without music,
> dance, and theater? Donate or volunteer in the arts today at Network
> for Good! http://us.click.yahoo.com/TzSHvD/SOnJAA/79vVAA/bGYolB/TM
> --------------------------------------------------------------------~-
> > 
> 
> Be sure to visit the group home and check for new Links, Files, and
> Photos: http://groups.yahoo.com/group/Homebrew_PCBs
> 
> If Files or Photos are running short of space, post them here:
> http://groups.yahoo.com/group/Homebrew_PCBs_Archives/ 
> Yahoo! Groups Links
> 
> 
> 
> 
> 
>

Nice Chart:

Just what the Doctor Ordered. This will look real good in my new Tech
Notebook I started last night. Feels good to be back in the saddle
again. Now to do what I didn't do before and to go where I dared not
once go.

7&3 fer nw,
KE5CTY (old calls WB5ZQU - WY5L)
http://www.qsl.net/ke5cty/
Code may be dying but the pioneering spirit that put the code there in
the first place is still going strong.

-----Original Message-----
From: Homebrew_PCBs@yahoogroups.com
[mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of Bob & Linda Gardner
Sent: Friday, June 10, 2005 2:32 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] setting the rings on carbide drills


Stefan,

For a drill bit size chart try:

<http://drillbitcity.com/images/charts/drill_bit_comp_chart.pdf>

Bob

> Hi,
> 
> 
> My drills are all without the little plastic rings, so i bought a 
> small  lot with rings in the hopes of using them. How can those rings 
> be set? does it work with a metal tube and a little  hammer?
> 
> Also, if somebody knows a inch/metric PCB drill conversion table (with

> the  #), please let me know. it isn't that important as i can easily 
> calculate  it myself, but if you know a url...
> 
> ST
> 
> 
> ------------------------ Yahoo! Groups Sponsor 
> --------------------~--> What would our lives be like without music, 
> dance, and theater? Donate or volunteer in the arts today at Network 
> for Good! http://us.click.yahoo.com/TzSHvD/SOnJAA/79vVAA/bGYolB/TM
> --------------------------------------------------------------------~-
> > 
> 
> Be sure to visit the group home and check for new Links, Files, and
> Photos: http://groups.yahoo.com/group/Homebrew_PCBs
> 
> If Files or Photos are running short of space, post them here: 
> http://groups.yahoo.com/group/Homebrew_PCBs_Archives/
> Yahoo! Groups Links
> 
> 
> 
> 
> 
> 






Be sure to visit the group home and check for new Links, Files, and
Photos: http://groups.yahoo.com/group/Homebrew_PCBs

If Files or Photos are running short of space, post them here:
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On Fri, 10 Jun 2005 21:31:38 +0200, Bob & Linda Gardner  
<gardner.bob@...> wrote:

> Stefan,
> For a drill bit size chart try:
> <http://drillbitcity.com/images/charts/drill_bit_comp_chart.pdf>
> Bob


Thanks, that's what i needed. Thanks als for the other offers.

As for moving the rings, i will still try a hammer, because i'm pigheaded  
;-)
When i  have broken a bit i will perhaps make a jig that can be used in a  
vice or something. I only see how to move the ring in one way, anyway, i  
gueess one must start all over if one moved it too far.


Thinking about it, a simple mechanism with a screw would be easy to make.  
take a piece of tubing, just bigger than the ring, and either cut a  
screwthread inside it or braze a nut to it. on the other end mount a  
washer that has a inner diameter smaller than the plastic ring outer  
diameter. you slip the tubing piece over the bit from the front, so that  
the washer sits against the ring, and then simply screw the screw in to  
pull the ring back on the shaft, the screw pressing against the end of the  
drill. should allow precise adjustment, just add wings to screw and tube  
for easy turning by hand. theoretically one might be able to drill out the  
screw to allow pressure from the other side also, but probably it would  
cause beaking of the drill if all is not straight. Probably it is easier  
to make two screwsm one with a flat or slightly depressed end to normally  
push the shaft along, and one with a stud slightly smaller than a drill  
shaft, to press the ring all the way off (of one has moved it too far or  
it must go on another bit).


Varitions to this design could be contemplated, like allowing to insert  
the drill from the side so it isn't necessary to take the tool apart  
completely, but it would be more difficult to make.


Now i wonder what professional bit grinding shops or manufacturers use?


ST

In a message dated 6/10/2005 4:21:28 P.M. Central Daylight Time,  
stefan_trethan@... writes:

As for  moving the rings, i will still try a hammer


As I already said, simply use a (turned-OFF!)  drill-press!


[Non-text portions of this message have been removed]

On Sat, 11 Jun 2005 06:54:21 +0200, <JanRwl@...> wrote:

>
> As I already said, simply use a (turned-OFF!)  drill-press!


yes, as i already said, there are are several minor factors that don't  
allow that.
One beeing i do not own a dril press.

See my other replys for the idea with the scew adjuster, i think it is  
very reasonable and i will make one today.


ST

Stefan:
 
I am curious WHY you want to "adjust" these plastic rings, as  they are used 
in professional PCB drilling ONLY to support the bit in a magazine  for the 
automatic bit-insertion step in CNC operations using more than one size  bit, 
AND, as a place to print the diameter of the bit.  That is, the  precise 
vertical location of the ring is not used as any "depth reference"; nor  would that 
"stay", anyway!


[Non-text portions of this message have been removed]

On Sat, 11 Jun 2005 17:21:58 +0200, <JanRwl@...> wrote:

> Stefan:
> I am curious WHY you want to "adjust" these plastic rings, as  they are  
> used
> in professional PCB drilling ONLY to support the bit in a magazine  for  
> the
> automatic bit-insertion step in CNC operations using more than one size   
> bit,
> AND, as a place to print the diameter of the bit.  That is, the  precise
> vertical location of the ring is not used as any "depth reference"; nor   
> would that
> "stay", anyway!


I will use the rings as a precise depth reference ;-)))

No, seriously, i want to make bit changing easier. it is a pain to adjust  
the drill in a pivoting press to just drill through the PCB each time. I  
will set the ring so it just sits against the collet and i don't need to  
care for anything.

It will also be of help with the CNC drill later i suppose. I only need  
like 0.5mm accuracy.


ST

Just want to let you know the idea with the screw works well.

A M10 nut soldered to a short piece of tubing, and on the other end a  
washer.
The drill bit is inserted through the nut, with business end forward so it  
sticks out the washer.
Then a screw is turned into the nut to push the shaft forward.

I made a second screw with a 3mm stud on the tip, which is used to push  
the drill shaft out of the ring all the way.
For putting a ring on a previously empty drill it is helpful to make a  
screw with a hole in the tip, to hold the drill.
The screw is large enough so you can just turn it with your hand and  
overcome the friction of the ring.

Build time: 30 minutes.
Drawback: can not put rings on drills bigger than the standard shaft  
diameter, as the ring does of course not go over the sharp end. I will not  
want to exert pressure on the business end even of a big drill as it will  
surely break. not a problem as i drill them mounting holes with another  
drill anyway where the rings are not needed.

Possible modifications:
If you use a thread coupler (long nut) instead of the nut and tubing you  
have less work to do. i had none that size.
Soft solder is enough strength-wise. If you have a lathe you can make the  
nut/tubing/washer one piece.

ST

In a message dated 6/11/2005 10:47:00 A.M. Central Daylight Time,  
stefan_trethan@... writes:

seriously, i want to make bit changing easier. it is a pain to  adjust  
the drill in a pivoting press to just drill through the PCB  each time. I  
will set the ring so it just sits against the collet  and i don't need to  
care for anything.

It will also be of  help with the CNC drill later i suppose. I only need  
like 0.5mm  accuracy.



IC!  That makes it clear.  Logical.  


[Non-text portions of this message have been removed]

I was wondering if any of you have come up with a simple automated tool
changing system, or have seen one that is within a "simple man's" reach to
fabricate.

Robert
:)



-----Message d'origine-----
De : Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] De
la part de JanRwl@AOL.COM
Envoyé : juin 12 2005 01:16
À : Homebrew_PCBs@yahoogroups.com
Objet : Re: [Homebrew_PCBs] setting the rings on carbide drills


 
In a message dated 6/11/2005 10:47:00 A.M. Central Daylight Time,  
stefan_trethan@gmx.at writes:

seriously, i want to make bit changing easier. it is a pain to  adjust  
the drill in a pivoting press to just drill through the PCB  each time. I  
will set the ring so it just sits against the collet  and i don't need to  
care for anything.

It will also be of  help with the CNC drill later i suppose. I only need  
like 0.5mm  accuracy.



IC!  That makes it clear.  Logical.  


[Non-text portions of this message have been removed]




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> I was wondering if any of you have come up with a simple automated
tool changing system, or have seen one that is within a "simple man's"
reach to fabricate. Robert <

Robert, hi,

I've got a CNC Sherline tabletop mill; is this the type of machine you
hope to find an tool changing system for? If so, here's a note from
the Sherline Yahoo group that I saved. Hope it's helpful (but, I
haven't visited the site since the date of the post):
......................................................
"onecooltoolfool" 
Jan 23, 2004 
Mini Automatic Tool Changer                                          
                                                                     
                                    

Home Shop Accessories Inc. of Louisville has released plans and kits
for the first, fully automatic tool changer designed for miniature
machining and CNC applications. The tool changer is a complete,
self-contained spindle and turret that was specifically designed to
work with Sherline, Taig, MaxNC, and other mini CNC milling machines.

This six-station sequential tool changer will take your hobby CNC to
the next level of performance and productivity. The mechanism can be
used in full, or semi-automatic mode and features a six-station tool
turret and pneumatic drawbar.

The tool changer can function with CNC or manual machines and requires
only one, single actuation signal, either manual or remote, to execute
a tool change cycle.

Highlights:

One channel of digital I/O (no subroutine programming or separate
controller)
Multiple kit levels available for beginner thru advanced
Rapid tool change, 1 to 3 second cycle time
Full or semi automatic operation
Fast growing community of builders online at Yahoo minitoolchanger group
Secure, fast, online ordering with PayPal, receive your plans in a few
minutes!

www.homeshopaccessories.com               
Join in the mini tool changer discussion online at

http://groups.yahoo.com/group/minitoolchanger

Woohoo, thanks, that's awesome,  gonna check that site out.

Nope, not for a conventional machine, I am building my own which will run
off Mach 2.  But I'd love to automate the tool changing, so I wouldn't mind
spending a little time learning what kind of attachment I need for the job.
I'm in the design phase now, I'd like to integrate a tool-changer right now
if it's simple.

Robert
:)



-----Message d'origine-----
De : Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] De
la part de Brian Chapman
Envoyé : juin 12 2005 12:15
À : Homebrew_PCBs@yahoogroups.com
Objet : [Homebrew_PCBs] Re: Automatic bit holder - was setting the rings on
carbide drills


> I was wondering if any of you have come up with a simple automated
tool changing system, or have seen one that is within a "simple man's" reach
to fabricate. Robert <

Robert, hi,

I've got a CNC Sherline tabletop mill; is this the type of machine you hope
to find an tool changing system for? If so, here's a note from the Sherline
Yahoo group that I saved. Hope it's helpful (but, I haven't visited the site
since the date of the post):
......................................................
"onecooltoolfool" 
Jan 23, 2004 
Mini Automatic Tool Changer                                          
                                                                     
                                    

Home Shop Accessories Inc. of Louisville has released plans and kits for the
first, fully automatic tool changer designed for miniature machining and CNC
applications. The tool changer is a complete, self-contained spindle and
turret that was specifically designed to work with Sherline, Taig, MaxNC,
and other mini CNC milling machines.

This six-station sequential tool changer will take your hobby CNC to the
next level of performance and productivity. The mechanism can be used in
full, or semi-automatic mode and features a six-station tool turret and
pneumatic drawbar.

The tool changer can function with CNC or manual machines and requires only
one, single actuation signal, either manual or remote, to execute a tool
change cycle.

Highlights:

One channel of digital I/O (no subroutine programming or separate
controller)
Multiple kit levels available for beginner thru advanced
Rapid tool change, 1 to 3 second cycle time
Full or semi automatic operation
Fast growing community of builders online at Yahoo minitoolchanger group
Secure, fast, online ordering with PayPal, receive your plans in a few
minutes!

www.homeshopaccessories.com               
Join in the mini tool changer discussion online at

http://groups.yahoo.com/group/minitoolchanger  





Be sure to visit the group home and check for new Links, Files, and Photos:
http://groups.yahoo.com/group/Homebrew_PCBs

If Files or Photos are running short of space, post them here:
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